2016 MERCEDES-BENZ C-CLASS CABRIOLET open bonnet

Display messages
Possible causes/consequences and
M
MSolutions ?
Coolant Stop vehi‐ Coolant Stop vehi‐
cle Switch engine cle Switch engine
off off The coolant is too hot.
A warning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine has
overheated can cause any fluids that may have leaked into the engine compartment to catch fire.
In addition, steam from an overheated engine can cause serious
burns, which can occur just by opening the bonnet.
There is a risk of injury!
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 159).
X Wait until the engine has cooled down.
X Make sure that the air supply to the engine radiator is not blocked,
e.g. by frozen slush.
X Do not start the engine again until the display message goes out and
the coolant temperature is below 120 †. The engine may otherwisebe damaged.
X Pay attention to the coolant temperature gauge.
If the temperature increases again:
X Consult a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †. #
See Owner's Manual See Owner's Manual The battery is no longer being charged.
A warning tone also sounds.
Possible causes:
R faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
! Do not continue driving. The engine could otherwise overheat.
X Stop the vehicle immediately, paying attention to road and traffic
conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 159).
X Consult a qualified specialist workshop. Display
messages
255On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Clutch overheated
Clutch overheated
Avoid pulling away Avoid pulling away
Engage/disengage Engage/disengage
clutch quickly if clutch quickly if
req. req. The clutch is under considerable load and the permitted operating
temperature has been exceeded. A warning tone also sounds.
Avoid frequent pulling away and driving at walking pace over longer
distances.
X Stop the vehicle, paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 159).
X Leave the engine running.
The clutch is cooled more quickly with the engine running.
or X If possible, drive on at a steady speed.
X Remove your foot from the clutch pedal and do not allow the clutch
to slip.
The clutch may also cool down during the journey.
It may take several minutes for it to cool down. When the clutch has
cooled down, the display message disappears. The clutch is fully
operational again. N The boot lid is open.
X Close the boot lid. M The bonnet is open. A warning tone also sounds.
G WARNING
The open bonnet may then block your view when the vehicle is in
motion.
There is a risk of an accident.
X Stop the vehicle safely as soon as possible, paying attention to road
and traffic conditions.
X Secure the vehicle against rolling away (Y page 159).
X Close the bonnet. Active bonnet mal‐ Active bonnet mal‐
function See Own‐ function See Own‐
er's Manual er's Manual The active bonnet (pedestrian protection) is not active due to a mal-
function or because it has already been triggered.
X Consult a qualified specialist workshop. C At least one door is open. A warning tone also sounds.
X Close all doors. _
Front left seat Front left seat
backrest backrest
not
notlocked
locked
or Front right seat
Front right seat
backrest not locked
backrest not locked The driver's or front-passenger's seat backrest is not engaged. A
warning tone also sounds.
X Push the backrest back until it engages. Display
messages
269On-board computer and displays Z

Warning/
indicator
lamp
N N
Signal type
Possible causes/consequences and M
M Solutions ?
N
The red coolant warning lamp comes on while the engine is running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled sufficiently.
X Observe the additional display messages on the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Secure the vehicle against rolling away (Y page 159).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and top up the coolant, making sure to observe the
warning notes (Y page 312).
X If you have to top up the coolant frequently, have the engine cooling system
checked.
X Make sure that the air supply to the engine radiator is not blocked, e.g. by frozen
slush.
X Do not start the engine again until the coolant temperature is below 120 †. The
engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in mountainous terrain
and stop-start traffic. ?
N
The red coolant warning lamp comes on while the engine is running. A warning
tone also sounds.
The coolant temperature has exceeded 120 †. The airflow to the engine radiator
may be blocked or the coolant level may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine is overheated
can cause any fluids that may have leaked into the engine compartment to catch fire.
In addition, steam from an overheated engine can cause serious burns, which can
occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages on the multifunction display.
X Stop the vehicle immediately, paying attention to road and traffic conditions,
and switch off the engine.
X Secure the vehicle against rolling away (Y page 159).
X Leave the vehicle and keep a safe distance from the vehicle until the engine has
cooled down.
X Check the coolant level and top up the coolant, making sure to observe the
warning notes (Y page 312).
X If you have to top up the coolant frequently, have the engine cooling system
checked. 280
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Engine compartment
Bonnet
Important safety notes G
WARNING
An unlocked bonnet may open up when the
vehicle is in motion and block your view. There is a risk of an accident.
Never unlock the bonnet when driving. Before
every trip, ensure that the bonnet is locked. G
WARNING
When being opened and closed, the bonnet
may suddenly fall into the closed position.
There is a risk of injury to persons in the range of movement of the bonnet.
Open and close the bonnet only when nobody
is in the range of movement. G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade. G
WARNING
There are moving components in the engine
compartment. Certain components may con-
tinue to move or suddenly move again even
after the ignition has been switched off, e.g.
the radiator fan. There is a risk of injury.
If you have to carry out work in the engine
compartment:
R switch off the ignition
R never touch the dangerous areas surround-
ing moving components, e.g. the rotation
area of the fan R
remove jewellery and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts.
Active bonnet (pedestrian protection) Operating principle
! An active bonnet that had been triggered
must be repaired at a qualified specialist
workshop. The active bonnet function will
then be available again. The additional pedes- trian protection provided by the active bonnet
will then be restored.
The active bonnet is available only in certain
countries.
The active bonnet can reduce the risk of injury to pedestrians in certain accident situations. Rais-
ing the active bonnet increases the clearance to hard components, such as the engine.
If the active bonnet has been triggered, it is
raised at the rear in the area around the hinges by approximately 80 mm. The active bonnet is
triggered by pyrotechnics.
For the drive to the workshop, reset the trig-
gered active bonnet yourself. If the active bon-
net has been triggered, pedestrian protection
may be limited.
Resetting G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. 308
Engine compartmentMaintenance and care

X
With your hand flat, push down the active
bonnet :in the area around the hinges on
both sides (arrows).
Do so until you feel the active bonnet :
engage.
If you can raise the active bonnet slightly at the rear in the area around the hinges, it is not
engaged correctly. Repeat the step.
Opening the bonnet G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that the windscreen wipers are
not folded away from the windscreen. Other-
wise, you could damage the windscreen wip-
ers or the bonnet. X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately 40 cm, the bonnet is opened and held open automat-
ically by the gas-filled struts.
Closing the bonnet X
Lower the bonnet and let it fall from a height
of approximately 20 cm.
X Check that the bonnet has engaged properly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close it
with a little more force. Radiator
Do not cover up the radiator. Do not use thermal mats, insect protection covers or anything sim-
ilar. Otherwise, the values of the European on-
board diagnostics may be affected. Some of
these values are required by law and must
always be correct. Engine compartment
309Maintenance and care Z

Engine oil
Important safety notes G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the components descri- bed in the following. G
WARNING
There are moving components in the engine
compartment. Certain components may con-
tinue to move or suddenly move again even
after the ignition has been switched off, e.g.
the radiator fan. There is a risk of injury.
If you have to carry out work in the engine
compartment:
R switch off the ignition
R never touch the dangerous areas surround-
ing moving components, e.g. the rotation
area of the fan
R remove jewellery and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts. G
WARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil does not spill out
over the filler neck. Allow the engine to cool
down and thoroughly clean the components
that have come into contact with engine oil
before you start the engine. G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury. Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade.
General notes Depending on your driving style, the vehicle
consumes up to 0.8 l of oil per 1000 km. The oil
consumption may be higher than this when the
vehicle is new or if you frequently drive at high
engine speeds.
Depending on the engine, the oil dipstick may beinstalled at different locations.
To check the oil level:
R park the vehicle on a level surface
R the engine should be switched off for approx-
imately five minutes if the engine is at normal
operating temperature
R All vehicles (except Mercedes-AMG C 63
and Mercedes ‑AMG C 63 S):if the engine is
not at normal operating temperature, e.g. if
the engine was started only briefly, wait
approximately 30 minutes before carrying out the measurement
Mercedes ‑AMG C 63 and Mercedes ‑AMG C
63 S: The oil level must only be checked when
the engine is at normal operating temperature.
Checking the oil level using the oil dip-
stick Check the oil level with the oil dipstick (exam-
ple)
X Pull oil dipstick :out of the dipstick tube.
X Wipe off oil dipstick :.310
Engine compartmentMaintenance and care

cap, you could be scalded if hot coolant
sprays out. There is a risk of injury.
Let the engine cool down before you open the cap. Wear gloves and eye protection. Open
the cap slowly to release the pressure. G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade.
Checking the coolant level Check the coolant level (example)
X Park the vehicle on a level surface.
Check the coolant level only if the vehicle is
on a level surface and the engine has cooled
down.
X Turn the key to position 2in the ignition lock
(Y page 133).
or
X Press the Start/Stop button twice on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function (Y page 133).
X Check the coolant temperature display on the
instrument cluster (Y page 221).
The coolant temperature must be below
70 †. X
Turn the key to position 0in the ignition lock
(Y page 133).
or X Press the Start/Stop button once on vehicles
with KEYLESS-GO or the KEYLESS-GO start
function (Y page 133).
X Slowly turn cap :half a turn anti-clockwise
and allow excess pressure to escape.
X Turn cap :further anti-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank ;.
If the coolant level is approximately 1.5 cm
above marker bar =in the filler neck when
warm, there is enough coolant in coolant
expansion tank ;.
X If necessary, top up with coolant that has
been tested and approved by Mercedes-Benz.
X Replace cap :and turn it clockwise as far as
it will go.
Further information on coolant (Y page 366).
Topping up the windscreen washer sys-
tem G
WARNING
If windscreen washer concentrate comes into contact with hot components of the engine or
the exhaust system, it can ignite. There is a
risk of fire and injury.
Make sure the windscreen washer concen-
trate does not come into contact with the filler neck. Topping up the windscreen washer system
(example)312
Engine compartmentMaintenance and care

Electrolyte or battery acid is corro-
sive. Avoid contact with the skin,
eyes and clothing.
Wear suitable protective clothing; in
particular, gloves, an apron and a
face mask.
Immediately rinse electrolyte or acid
splashes off with clean water. Con-
sult a doctor if necessary. Wear eye protection.
Keep children at a safe distance.
Observe this Owner's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you use only batteries that have
been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehicle
occupants from suffering acid burns should the battery be damaged in the event of an accident.
In order for the battery to achieve the maximum possible service life, it should always be suffi-
ciently charged.
Like other batteries, the vehicle battery may
discharge over time if you do not use the vehicle.In such cases, have the battery disconnected ata qualified specialist workshop. However, you
can also charge the battery with a charger rec-
ommended by Mercedes-Benz. For more infor-
mation, please contact a qualified specialist
workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for an exten-
ded period. Consult a qualified specialist work-
shop if you wish to leave your vehicle parked up for a long period of time.
When you park the vehicle, remove the key if you
do not require any electrical consumers. The
vehicle will then use very little energy, thus con- serving battery power. Charging the 12 V battery
Vehicles with a lithium-ion battery:
! Only use battery chargers with a maximum
charging voltage of 14.4 V.
All ve hicles except vehicles with a lithium-
ion battery:
! Only use battery chargers with a maximum
charging voltage of 14.8 V. G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not breathe in any battery gases. Do not
lean over the battery. Keep the batteries out
of the reach of children. Immediately rinse off
battery acid thoroughly with plenty of clean
water and seek medical attention at once. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
All vehicles: ! Only charge the battery using the jump-start
connection point.
The jump-starting connection point is in the
engine compartment (Y page 333).
X Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order as
when connecting the donor battery in the
jump-starting process (Y page 333).332
Battery (vehicle)Breakdown assistance